Recursive BOM Array Method

gistfile1.php

    /**
     * Returns all of the assemblies items in an
     * easy to work with array.
     *
     * @param bool $recursive
     *
     * @return array
     */
    public function getAssemblyItemsList($recursive = true, $depth = 0)
    {
        $list = [];

        $items = $this->getAssemblyItems();

        $level = 0;

        $depth++;

        foreach ($items as $key => $item) {
            $list[$level] = [
                'id' => $item->id,
                'name' => $item->name,
                'metric_id' => $item->metric_id,
                'category_id' => $item->category_id,
                'quantity' => $item->pivot->quantity,
                'depth' => $depth,
            ];

            if ($item->is_assembly && $recursive) {
                $list[$level]['parts'] = $item->getAssemblyItemsList(true, $depth);
            }

            $level++;
        }

        return $list;
    }